Voltage regulators, such as DC-to-DC voltage converters, are used to provide stable voltage sources for various electronic systems. Efficient DC-to-DC converters are particularly needed for battery management in low power devices (e.g., laptop notebooks, cellular phones, etc.). A switching voltage regulator generates an output voltage by converting an input DC voltage into a high frequency voltage, and then filtering the high frequency input voltage to generate the output DC voltage. Specifically, the switching regulator includes a switch for alternately coupling and decoupling an input DC voltage source (e.g., a battery) to a load (e.g., an integrated circuit (IC)). An output filter, typically including an inductor and a capacitor, may be coupled between the input voltage source and the load to filter the switch output, and thus provide the output DC voltage. A controller (e.g., a pulse width modulator (PWM), a pulse frequency modulator, etc.) can be used to control the switch to maintain a substantially constant output DC voltage.
Switching voltage regulators are widely used in many of today's power management applications due to its relatively high power conversion efficiency. However, good transient responses may be difficult to achieve in switching regulators, as compared to linear regulators, because of the inclusion of an inductor-capacitor (LC) filter. In addition, the particular switching actions found in switching regulators may also generate more electromagnetic interference (EMI) type noise.